The present invention relates generally to respiratory catheter systems utilizing a heat and moisture exchanger, and particularly to an adaptor for use in such systems.
There are a number of different circumstances in which it is necessary for a person to have an artificial airway, such as a tracheostomy tube, placed in his or her respiratory tract. As used herein, the phrase xe2x80x9cartificial airwayxe2x80x9d includes devices such as tracheostomy tubes, endotracheal tubes and the like. Artificial airways keep the patient""s natural airway open so that adequate lung ventilation can be maintained. In particular situations, the artificial airway must be left in the patient for a prolonged period of time. For example, many persons suffering severe neck or head trauma use a tracheostomy tube in conjunction with mechanical ventilation during extended recovery and rehabilitation periods.
When an artificial airway is used, it is critical that respiratory secretions be periodically removed. This is typically accomplished by the use of a respiratory suction catheter that is advanced into and through the tracheostomy tube. As the suction catheter is withdrawn, a negative pressure (or vacuum) is applied to draw mucus and other secretions from the patient""s airways and the interior of the artificial airway. While a substantial amount of mucus and other secretions will be withdrawn through the lumen of the suction catheter, a portion of the mucus and other secretions will remain as a film on the outside of the catheter.
In a closed suction catheter assembly (for example as set forth in U.S. Pat. Nos. 3,991,762 and 4,569,344), the catheter may be enveloped by a protective sleeve and include a valve mechanism disposed near the vacuum source. These features reduce the risk of contamination to both the patient and the care-giver.
In normal breathing, the structures of the nose and sinus passages serve to heat and moisturize inhaled air. In situations where a patient requires mechanical ventilation on a periodic basis, it is common to place a heat and moisture exchanger (HME) on the proximal end of the artificial airway after removal of the mechanical ventilator. This type of placement is commonly done with patients who are able to breathe on their own for an extended period of time. In such systems and as used herein, xe2x80x9cproximalxe2x80x9d refers to the direction toward the clinician and xe2x80x9cdistalxe2x80x9d refers to the direction toward the patient.
The HME is intended to replicate these functions, of heating and moisturizing air, in patients having artificial airways. The HME is adapted to reduce heat and moisture loss from the respiratory system of the patient as the patient breathes. This is done by retaining within the HME heat and moisture from air which is exhaled through the HME, and by warming and moisturizing air that is inhaled through the HME. The HME typically includes a material, such as porous foam, that is enclosed within a housing or other structure.
To date, most HMEs have not been used in conjunction with a closed suction catheter assembly. Thus, prior to suctioning respiratory secretions from a patient, it may be necessary to remove the HME from the proximal end of the artificial airway so that a suctioning catheter may be advanced to the patient""s natural airways. Removal and attachment of the HME often causes discomfort to the patient and, during the period in which the HME has been removed, the patient is deprived of heat and moisture exchange and may be deprived of supplemental oxygen, if used.
Thus, there is a need for an inexpensive adaptor that enables a closed suction catheter to be easily and quickly attached to and removed from an HME that is mounted to an artificial airway while minimizing patient discomfort.
Various features and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
The present invention is generally directed to an adaptor for connecting a closed suction catheter assembly to an HME mounted on an artificial airway, such as a tracheostomy tube. In addition, the present invention is directed to a closed suction catheter system containing the adaptor and a closed suction catheter assembly. The adaptor of the present invention does not interfere with patient breathing.
The adaptor has a first end that is adapted to be in communication with the closed suction catheter assembly. The adaptor may be removably or non-removably engaged with the catheter assembly. The adaptor also has a second end which is adapted to engage the heat and moisture exchanger. Further, there is a channel formed through the adaptor. This channel allows an aspirating catheter of the closed suction catheter assembly to be moved through the adaptor. The aspirating catheter can then also be moved through an aperture formed through the heat and moisture exchanger.
An adaptor cover may also be provided for use with the closed suction catheter system. The cover is configured to selectively isolate the closed suction catheter assembly from the environment, and to facilitate cleaning of the catheter after suctioning.
The present invention may also provide an alternative embodiment of an adaptor for connecting a closed suction catheter assembly to an HME. The adaptor includes a first end configured for attachment to a closed suction catheter assembly, and a second end including a retainer capable of engaging the HME. The adaptor is configured for advancement of a catheter therethrough. The retainer may include a ring, for example a circular or elliptical ring member, having a wall configured to encircle and releasably engage the HME.
Furthermore, if a ring retainer is included in the adaptor, the ring may include a pair of oppositely disposed apertures located on first and second portions of the ring. The apertures are configured to engage the HME. Moreover, the retaining ring may also include bowed outward third and fourth portions oppositely disposed from each other on the ring with the bowed outward third and fourth portions disposed between the first and second portions on the ring. These bowed third and fourth portions may be configured such that, as they are urged inwardly toward each other, the first and second portions are urged to move outwardly away from the HME, thereby disengaging the first and second portions from the HME.
The retainer of the adaptor may be formed such that the first portion and the second portion are defined by apertures for receiving external projections of the HME. Alternatively, the retainer may include at least one L-shaped channel configured for receiving external projections of the HME. In one embodiment, the adaptor may also include an annular projection configured for engaging a valve in the top of the HME.
The present invention may also form an adaptor assembly for connecting a closed suction catheter assembly to an HME. The adaptor assembly includes an adaptor having a first end configured for attachment to a closed suction catheter assembly; and a second end including a retainer configured for engaging the HME and positioning the closed suction catheter assembly with respect to the HME. The adaptor is configured for advancement of a catheter therethrough. The adaptor assembly may also contain an annular projection defining a channel through which a catheter of the closed suction catheter assembly may be advanced. The adaptor assembly may also include an adaptor cover configured for attachment to the annular projection.
The adaptor cover can take on various configurations. For example, the cover may have a cylindrical wall formed therein with at least one opening formed in the wall. A cap may be provided with the cover for covering the opening.
In another embodiment, the adaptor assembly includes at least one arm formed in the retainer, wherein the arm is capable of engaging the HME. For example, the retainer may include at least two arms oppositely disposed from each other wherein each arm is capable of engaging the HME.
In addition, at least one arm may include an aperture capable of receiving a projection of the HME. Furthermore, at least one arm may include a surface member capable of engaging the HME. The adaptor assembly may include a base formed in the retainer wherein each arm is pivotally connected to a base.
The present invention is also directed to a closed suction catheter system. This system includes a closed suction catheter assembly having a catheter and a protective sleeve enveloping the catheter. The closed suction catheter assembly includes a distal end; and an adaptor connected to this distal end capable of engaging a proximal end of an HME.